The horseshoe arch (
Arabic: قوس حدوة الحصان;
Spanish: arco de herradura), also called the Moorish arch and the keyhole arch, is a type of arch in which the circular curve is continued below the horizontal line of its diameter, so that the opening at the bottom of the arch is narrower than the arch's full span.[1][2][3] Evidence for the earliest uses of this form are found in
Late Antique and
Sasanian architecture, but it became emblematic of
Islamic architecture, especially
Moorish architecture. It also made later appearances in
Moorish Revival and
Art Nouveau styles. Horseshoe arches can take rounded, pointed or
lobed form.
Another possible origin of the horseshoe arch motif is India, where
rock-cut temples with horseshoe arches are attested at an early period, though these were sculpted into rock rather than constructed.[10][4] For example, horseshoe arch shapes are found in parts of the
Ajanta Caves and
Karla Caves dating from around the 1st century BCE to 1st century CE.[11]
Horseshoe arches made of baked brick have been found in the so-called Tomb of the Brick Arches in
Aksum (present-day
Ethiopia), built during the
Kingdom of Aksum and tentatively dated to the 4th century CE.[10][12] In a 1991 publication, archeologist Stuart C. Munro-Hay suggests that these could be evidence that transmission of architectural ideas took place via routes not previously considered by scholars. He suggests that the brick-built horseshoe arches could have been an Aksumite innovation based on ideas transmitted via trade with India.[10]
According to Giovanni Teresio Rivoira, an archeologist writing in the early 20th century, the pointed variant of the horseshoe arch is of Islamic origin.[25] According to Rivoira, this type of arch was first used in the
Ibn Tulun Mosque,[25] completed in 879.[26]Wijdan Ali also describes this as the first systematic use of the pointed variant.[27] Horseshoe arches of a slightly pointed form were also used in
Aghlabid architecture of the 9th century,[28]: 45 including the
Great Mosque of Kairouan (circa 836) and the
Mosque of Ibn Khayrun (866).[29][30]
Development in the Iberian Peninsula and the Maghreb
It was in
Al-Andalus (on the
Iberian Peninsula) and western
North Africa (the
Maghreb) that horseshoe arches developed their characteristic form. Prior to the
Muslim invasion of Spain, the
Visigoths of the Iberian Peninsula used them in
their architecture.[31][7][32] Although it is possible that Andalusi architecture borrowed the horseshoe arch from Umayyad Syria, these local precedents make it just as likely that it developed locally instead.[33]: 43 The "Moorish" arch, however, was of a slightly different and more sophisticated form than the Visigothic arch, being less flat and more circular.[28]: 163–164 [33]: 43
The
Umayyads of Al-Andalus, starting with the
Emirate period, used horseshoe arches prominently and ubiquitously, often enclosing them in an alfiz (rectangular frame) to accentuate the effect of its shape.[28]: 45 This can be seen at a large scale in their major work, the
Great Mosque of Córdoba.[29] Its most distinctive form, however, was consolidated in the 10th-century during the
Caliphal period, as seen at
Madinat al-Zahra, where the arches consist of about three quarters of a circle and are framed in an alfiz.[34] The Córdoban style of horseshoe arch spread all over the Caliphate and adjacent areas, and was adopted by the successor Muslim emirates of the peninsula, the
taifas, as well as by the architecture of the Maghreb under subsequent dynasties. Its use remained especially consistent in the form of mosque mihrabs.[28]: 232
In the northern Iberian Peninsula, where
Asturias and other Christian kingdoms ruled, the use of horseshoe arches continued under the influence of previous Visigothic architecture and of contemporary Islamic architecture.[35] The addition of an alfiz around horseshoe arches was one detail more specifically borrowed from Islamic styles.[35] Starting in the 9th century, some
Mozarabs (Christians living under Muslim rule) left al-Andalus and settled in the northern Christian territories,[b] where they contributed to popularizing this form locally, as exemplified by
San Miguel de Escalada (10th century).[36][37][38] The Mozarabs also incorporated horseshoe arches into their art, such as in
illuminated manuscripts.[39][40]
Under the
Almoravids (11th-12th centuries), the first pointed horseshoe arches began to appear in the region and then became more widespread during the
Almohad period (12th-13th centuries). This pointed horseshoe arch is likely of North African origin.[28]: 234 Art historian
Georges Marçais attributed it in particular to
Ifriqiya (present-day
Tunisia), where it was present in earlier Aghlabid and
Fatimid architecture.[28]: 234
As Muslim rule retreated in Al-Andalus, the
Mudéjar style, which developed from the 12th to the 16th centuries under Spanish Christian rule, continued the tradition of horseshoe arches in the Iberian Peninsula.[41] Horseshoe arches also continued to be used in the Maghreb, in the
architecture of Morocco,
Algeria, and
Tunisia.[42][28]
Church of Santa Eulalia de Bóveda near Lugo, Spain (4th-5th century),[43] early Christian or Visigothic period
Horseshoe arches were also common in
Ghurid and
Ghaznavid architecture (11th-13th centuries) in
Central Asia, though in this region they had sharp pointed apexes, in contrast with those of the western Islamic world. Sometimes they were cusped or given multifoil flourishes.[47] Around the same time or not long afterward, they begin to appear as far east as
India,[47] in
Indo-Islamic architecture, such as in the
Alai Darwaza gatehouse (dating from 1311) at the
Qutb Complex in
Delhi,[48] though they were not a consistent feature in India.
Some pointed arches with a slightly horseshoe shape appear in
Ayyubid architecture in Syria.[49] It appears, exceptionally, in some instances of
Mamluk architecture. For example, it appears in some details of the
Sultan Qalawun Complex in Cairo, built in 1285.[50] Andalusi-style horseshoe arches are also found alongside the minaret of the Mosque of Ibn Tulun in Cairo, probably dating from 13th-century renovations ordered by
Sultan Lajin to the older 9th-century mosque.[51]
Use in Moorish revival architecture
In addition to their use across the Islamic world, horseshoe arches became popular in Western countries in
Moorish Revival architecture, which became fashionable in the 19th century. They were widely used in Moorish Revival synagogues.[53][54] They were employed in the
Neo-Mudéjar style in Spain, another type of Moorish Revival style.[55] They are used in some forms of
Indo-Saracenic Revival architecture, a 19th-century style associated with the
British Raj.[55]
^In a 1997 study, art historians Thomas F. Mathews and Annie-Christine Mathews Daskalakis argued that this feature of Cappadocian architecture was likely derived later from contemporary architecture in the neighboring Islamic world.[16][17] Historians J. Eric Cooper and Michael J. Decker expressed a similar view in which the use of arcades of horseshoe arches on Cappadocian façades was inspired by Islamic architectural models, reflecting the cosmopolitan nature of Cappadocia in this era.[18] Multiple other scholars, such as Nicole Thierry, Robert Ousterhout, and Philipp Niewöhner cite Mathews and Mathews Daskalakis in their discussion of horseshoe arches in the region but they suggest that the evidence points instead to earlier antecedents in
Late Antique architecture.[13][14][15]
^The term "Mozarabic" is also applied to the culture of communities outside Al-Andalus, in the northern Christian territories, where Christians from al-Andalus immigrated and resettled, particularly in the 10th century. However, the term reboplación, among other alternatives, can be used to refer to this culture.[35]
^
abcM. Bloom, Jonathan; S. Blair, Sheila, eds. (2009). "Mozarabic". The Grove Encyclopedia of Islamic Art and Architecture. Oxford University Press.
ISBN9780195309911.
^M. Bloom, Jonathan; S. Blair, Sheila, eds. (2009). "Mudéjar". The Grove Encyclopedia of Islamic Art and Architecture. Oxford University Press.
ISBN9780195309911.
^de Palol, Pere (1998). "From Antiquity to the Middle Ages, Christianity and the Visigothic World". In Barral i Altet, Xavier (ed.). Art and Architecture of Spaiin. Bulfinch Press. p. 64.
ISBN0821224565.
^Borrás Gualís, Gonzalo M.; Lavado Paradinas, Pedro; Pleguezuelo Hernández, Alfonso; Pérez Higuera, María Teresa; Mogollón Cano-Cortés, María Pilar; Morales, Alfredo J.; López Guzman, Rafael; Sorroche Cuerva, Miguel Ángel; Stuyck Fernández Arche, Sandra (2019).
"IX.1.c Church of San Roman". Mudéjar Art: Islamic Aesthetics in Christian Art. Museum With No Frontiers, MWNF (Museum Ohne Grenzen).
ISBN978-3-902782-15-1.
^
abM. Bloom, Jonathan; S. Blair, Sheila, eds. (2009). "Architecture; V. c. 900–c. 1250; A. Eastern Islamic lands.; 3. Afghanistan, Pakistan and India, c. 1050–c. 1250.". The Grove Encyclopedia of Islamic Art and Architecture. Oxford University Press.
ISBN9780195309911.
^M. Bloom, Jonathan; S. Blair, Sheila, eds. (2009). "Delhi". The Grove Encyclopedia of Islamic Art and Architecture. Oxford University Press.
ISBN9780195309911.
^M. Bloom, Jonathan; S. Blair, Sheila, eds. (2009). "Architecture; V. c. 900–c. 1250; B. Central Islamic lands.; 5. Syria, the Jazira and Iraq.". The Grove Encyclopedia of Islamic Art and Architecture. Oxford University Press.
ISBN9780195309911.
^M. Bloom, Jonathan; S. Blair, Sheila, eds. (2009). "Architecture; V. c. 900–c. 1250; C. Central Islamic lands.; 1. Egypt and Syria.". The Grove Encyclopedia of Islamic Art and Architecture. Oxford University Press.
ISBN9780195309911.